Role of the consultant in mass transitsystems

J.T. Edwards, B.Sc, F.C.G.I., F.I.C.E., F.C.I.T.

Indexing terms: Engineering administration & management, Transportation

Abstract: The main theme of the paper is the very wide range of disciplines involved in the design of a newmass transit system. The paper deals with the role of the consultant rather than discussing particular solutionsto technical problems. The importance of co-ordination of all electrical and mechanical engineering both withintheir systems and with the civil engineering and architectural design is explained and stressed. After outliningthe methods of route location used on early systems, the current way of assessing the potential number ofpassengers along the corridors is described. Factors determining the train size are outlined and the manyrequirements to be taken into account in designing the train identified. Particular mention is made of electricalaspects and some technical details, particularly those relating to power supply, are given. Emphasis is given toother matters in the domain of the electrical engineer, such as signalling, train control, telecommunications, farecollection and the environmental control system. Industrial and graphic design work by consultants is coveredin addition to the architectural aspects. The wide role of the consultant in the fields of financing, organisationand operation of the system are touched upon to show the diversity of professional expertise involved.

1 Introduction

My early professional life as a civil engineer was spent onthe design of power stations, initially on hydroelectricschemes followed by oil and coal-fired steam-driven gener-ators. Hydroelectric power stations involved a limited fieldof civil, electrical and mechanical engineering. Steampower stations brought in marine works and railway engi-neering including electric signalling, as well as a widerrange of civil engineering and co-operation with architects.

The complexity of a modern mass transit system notonly requires an even wider range of engineering disci-plines, but brings in urban and transport planning, a widerange of economic and financial criteria, and the organis-ational and operating aspects of management. The scopeof the consultancy involves people and not just physicaldesign, marking the key difference of the role of the consul-tant in mass transit systems from his role in designingpower stations. This paper endeavours to describe thatwide scope of consultancy services and to illustrate themultidisciplinary team needed for the design of a new inde-pendent system.

2 Is a mass transit system needed and justified?

Often the early lines were built by inventor-entrepreneurs,but the usual driving force for the initiative lay with theentrepreneur. They were followed soon after by themunicipality and, once the idea was seen to be welcomedby the public, the construction of further lines or adoptionof a mass transit railway became one of civic pride.

At a time when almost all the population had littlealternative transport and cities were expanding rapidly, noother proof was required to justify the need for a masstransit system. While meeting the need might have beenessential in that failure to meet it would have been a poli-tical disaster, it also had to be justified financially, whetherthe system was promoted by the entrepreneur or themunicipality.

During the first half of this century such simple yard-sticks became less readily applicable, partly, no doubt,

Paper 33O5A (M3, M4), first received 17th January and in revised form 15th June1984The author is with Freeman Fox & Partners, 25 Victoria Street (South Block),London SW1H OEX, England

because the profitable routes had already been developed.By 1950, the necessity for a more thorough evaluation ofall aspects became apparent. In particular, methods of esti-mating passenger demand by mode became essential.Specialist consultants had become recognised and theydeveloped the skills and techniques required.

3 Where should it run?

Early mass transit railways in major cities were built torun along the obvious natural corridors where the traveldemand was apparent. It was a natural consequence of thealready existing demand that surface transport in use hadbecome overloaded, causing traffic congestion and slowjourneys. This remains a fundamental criterion to justifyan inner-city line, a key function of old and new systems.

The development of large cities brought not only theneed for the inner-city system, but the commuter trafficfrom the outer residential areas had also to be carried.Meeting the demands of inner-city and commuter trafficalong natural existing corridors can be the basis of plan-ning a system in a major city. The paradox is that untilafter the Second World War, no major city had a systemwhich existed in the form which had been planned.London had, up to 1933, no less than fourteen railwaycompanies involved in building its system. Not all lineswere built in isolation and a practice of interworking andco-operation had been built up in meeting commercialinterests. Consultants had played a major role in thedesign and supervision of construction of the individuallines, but their influence on where they should run wasprobably not significant outside the engineering designfield. In passing, it is interesting to speculate on how theSouth Kensington to Westminster section of the DistrictLine (built 1865-68) was located in detail. Much of itslength was built by 'cut and cover' through built-up areas,requiring heavy compensation, whereas construction alongroads was much cheaper. Was the dense road traffic thecause of refusal to use the cheap route?

It was after the Second World War that the science andart of transport planning was developed by consultants.This produced a methodology for planning a completesystem and estimating traffic, so that estimates of revenuecould be made and alternatives evaluated for both costand benefit. Although the spur for the development of the

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techniques was the great postwar road programme, parti-cularly in towns, headed by the London traffic study, theiruse for rail studies was obvious. Throughout the world,this did not stop the politicians demanding that a circleline be built or a line from A to B, but increasingly thosecharged with providing the funds required consultants toinvestigate the justification of the expenditure.

As part of the detailed planning of where it should run,a decision has to be made on how it should run. Ideally,for environmental reasons and to avoid conflict with roadand pedestrian traffic, an urban railway should be out ofsight below ground. Such a line costs up to ten times morethan one at ground level (excluding land costs), and twiceas much as an elevated line. The consultant is usually facedwith determining the proportion of the three types whichwill give the minimum cost at publicly acceptableenvironmental levels. Baghdad is an exception where thegovernment decided the line should be wholly under-ground.

4 Assessing passenger demand, station locationsand passenger flows

The starting point for the assessment of the need and justi-fication for a mass transit system is the appraisal by theconsultant of urban and regional land-use and economicdevelopment plans for the area. This may involve the plan-ning departments of more than one authority, who may beworking on different time-scales. It has become customaryto adopt a planning period of 20 years ahead, because onthe one hand this is about the time taken to plan and builda system, and on the other hand it is about as far ahead asone can visualise economic and social developments whichcould have major effects on the plans. Indeed, bearing inmind that in the UK, for example, that period covers fouror five parliaments, the time is too long to forecast thepolitical influences. As a further example, during the plan-ning stage of the Hong Kong mass transit railway, a newtown of 500 000 inhabitants was assumed to be built, thencancelled and later reinstated, all within a period of fiveyears. It is an important role for the consultant to make anassessment of the most likely development plan, but moreoften the political influences are so difficult to determinethat alternative schemes have to be assessed under a widerange of assumptions to test their robustness and demon-strate justification.

The consultant can divide the whole area of the studyinto zones identifying the number of people who live andwork in each. From that basic information, the number ofjourneys for work, business and leisure along the varioustravel-demand corridors can be assessed. It is thus necess-ary to determine what proportions of journeys will bemade on the new rail system, and what will still be carriedby buses or other modes of travel. While this split can bemade on the basis of the travel times by each mode, thefare to be paid on each is a major influence. Public trans-port fares rarely cover total costs. Urban bus travel world-wide is subsidised, so making impossible a rivalcommercially-operated railway. It is not unusual for gov-ernments to lay down equality between fares at the plan-ning stage, which, while making the consultant's work inassessing passenger use straightforward, means planningthe system on a lossmaking basis which the governmentwill be unable to fund. The consultant can but identify themagnitude of the political problem.

Another intractable planning problem is becomingmore clearly apparent and frequent. Mass transit can beseen as an essential service to ensure the viability of a

major new urban development or urban regenerationpackage. Yet, commercially, the railway cannot be viablein the period during which the population and employ-ment will grow if the facility is provided. In Hong Kong'snew towns, in London's docklands, in the West Midlandsand elsewhere, this question, essentially one of political willand investment, appears to be recurring. The searchbecomes one for ancillary employment and developmentbenefits, to overcome the economic deficit arising from atransportation analysis. A new area for consulting and aca-demic consideration is thus arising, from which consultantswill doubtless produce methodologies to handle theproblem.

If a comprehensive transport study is made for thewhole city area, traffic on all modes can be estimated. Suchdata can be used to design an integrated transport systemwith bus routes feeding the railway, parking areas forprivate cars and easy interchange arrangements betweenthem. Sadly this is rarely achieved; Newcastle-upon-Tyneis a shining example of what can be done, whereas HongKong still suffers from private bus companies runningroutes competing with the public mass transit railway.

The travel demand assigned to the railway can be trans-lated into passenger flows in each direction along the oneor more railway lines forming the system. The preliminaryalignment of these lines on to maps enables potentialstation sites at points of high demand and easy access tobe identified. The flows in and out of each station can becalculated, thus forming the basis of passenger-flow plan-ning and hence the physical size of circulation areas,numbers of stairs and escalators, entry and exit barriersand general dimensions of the station. The flows alongeach line are the basis for determining the train size asdescribed in Section 10.

These passenger figures will be the numbers achievable.They will not be realised if the stations are too far apart,difficult to find, unattractive to use or not served frequent-ly. The transport planners can identify the potential traffic,but consultants in many other disciplines are required toensure that the traffic is obtained.

5 Train design

The time spent by passengers in the train may not be sig-nificantly longer than the time taken from street level toboarding the train and return; the train is part of the'people-moving' process. The train must be designed tomeet many requirements:

(a) it must have sufficient capacity to carry the estimatedpeak load at the stated service interval throughout theperiod of the peak. This necessitates the provision ofsurplus capacity to cope with the 'peak of the peak', and toallow for variations in loading which occur from car to carand from train to train

(b) the design of doors and of the train interior mustenable the passengers to board and alight within the per-mitted station dwell-time

(c) acceleration and braking rates must be sufficient forthe train to run to schedule (including coasting and stationstops) on the given route profile

(d) adequate comfort criteria relating to the proportionof sitting/standing room, ventilation, temperature/humidity, noise and vibration and jerk rate

(e) operational requirements such as manual or auto-matic control, one-man operation and arrangements foremergency detraining

(/) specified safety criteria relating to buffing load, fireresistance, electrical safety and resistance to derailment

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(g) weight, life span, reliability, ease of cleaning andmaintenance

(h) standardisation of equipment and economy incapital and operating costs.

Obviously, not all the above are readily compatible, andthe consultant will use his knowledge of transit systemsand car-building worldwide to write specifications which,while allowing manufacturers to make maximum use oftheir own experience and expertise, will ensure that thedesign of the train meets the above requirements. The con-sultant will continue his input during the detailed design ofthe train, reviewing each stage of the design to ensure com-pliance and compatibility.

6 Electrical engineering of train and power supply

The power supply voltages selected must be such as tominimise the cost of hardware required, while meeting thesafety criteria and providing the capacity to meet themaximum demand. Power supply must be designed foreconomy and integrity, but with sufficient flexibility andover-capacity to enable the service to be maintained at acommercial level, even under fault conditions.

The load from a new mass transit railway is of the orderof 40 MW to 80 MW, and so might appear to be sufficientto justify its own power station. A city large enough towarrant a mass transit railway (0-5M people or more) willnowadays be served by an electricity grid covering two ormore power stations, even if not connected to a nationalgrid. No new mass transit system is now likely to build itsown dedicated power station. The consultant will plan fora supply to be taken from two or more points on the 132kV, 161 kV or whatever the local grid voltage may be, andwill determine suitable locations for traction substations,to be supplied at 22 or 33 kV, where it will be transformedand rectified to a 750 or 1500 V DC supply. "Stations willprobably be supplied at 11 kV, preferably from twosources.

Various factors such as distribution and equipment volt-ages, transformer, rectifier/switchgear capacities, cablesizes, fault levels and protection and high or low-level trac-tion supply must all be evaluated, and again the consultantis in a unique position to ensure that the best balance of allthe factors is obtained.

Alternative forms of traction and control systems mustbe considered, balancing capital cost and weight againstoperating and maintainance costs.

Historically, mass transit system trains have been drivenby low-voltage DC motors, mounted on the bogies of carsand supplied with power from conductor rails. Recentdevelopments have included 'chopper' control equipment,3-phase induction motors, overhead lines, power supply athigher voltages and regenerative braking. Naturally, theproponents of the various schemes claim particular advan-tages, but the consultant's task must be to consider theperformance required, the relative cost of energy and hard-ware and the level of technology relevant to the systemconcerned. As in train design there is no single optimumsolution. It is the duty of the consultant to ensure that newschemes are only adopted if they are appropriate and, pref-erably, cost-effective. The detailed design of the equipmentremains the responsibility of the contractors.

Consider in more detail one aspect, the supply of trac-tion current to the train. The most widely used system is aconductor rail with a voltage of less than 750 V DC.Appreciable savings can be made in the number of tractionsubstations and cost of equipment by using a higher

voltage of 1500 V DC. There are few instances of voltagesover 1000 V being used with conductor rails. For 1500 VDC, overhead conductors are usual. If the line is elevatedor at ground level, the appearance of the overhead systemmay be an objection. If it is underground, larger tunnelsmay be needed. But an overhead system enables a supplyfor full lighting and air-conditioning to be maintained evenif passengers have to walk from a failed train. These andother factors require experience of international practiceand judgment, as well as technical ability, to evaluate theoptimum.

Modern rolling stock contains a large amount of aux-iliary equipment, such as air-conditioning or ventilatingequipment, lighting, power-operated doors and passengercommunication systems. The level of provision of thisequipment and the power supplies and necessary standbyfacilities must be considered within the context of theoverall operating philosophy.

7 Signalling, train control, telecommunicationsand fare collection

Modern mass transit systems have many similarities toprocess plants, with the obvious difference that passengerscannot be dealt with like chemicals. However, there is anincreasing amount of automation being installed in masstransit systems.

The trains may be automatically driven and althoughstill usually with an operator on board to perform certainduties and to take over in an emergency, the unmannedtrain is now in regular service in Lille and Kobe. Even themanual train service itself may be supervised by a com-puter which routes trains, regulates station departures andmaintains spacings between trains when delays occur.

The level of automation to be installed should be amatter of some considerable study. Factors to be con-sidered include capital and operating costs, local facilitiesand expertise, back-up facilities and reliability. There is anatural inclination on the part of both operators andmanufacturers towards automation, and the experience inLille seems to indicate no objection from the public. Theconsultant's role is to set an optimum level for the particu-lar system, always ensuring that safety is paramount.

Telecommunications which facilitate the passing of in-structions and information must be engineered to ensurethat capacity exists for use in an emergency: radio, CCTV,telephones and teleprinters are all likely to be used. Pass-engers need to be kept informed both routinely and in anemergency, and public-address systems and visual displaysare necessary. The interfacing and interlinking of all thesesubsystems can best be carried out by consultants with aknowledge of the total system requirements.

To prevent fraud and to reduce labour costs, automaticfare collection equipment handling from single flat farerides to stored-ride and stored-fare systems, is commonlyinstalled in new mass transit railways. There are manyproprietary systems, and the consultant must specify therequirements carefully to ensure that an over-expensive orunsuitable ready-made system is not installed.

8 Environmental control

In hot climates, air-conditioning of stations and trains maybe essential, and vast quantities of cool air may have to beforced through tunnels in emergency situations to preventunacceptable rises in temperature and shortage of fresh air.The environmental control system must ensure that suffi-cient oxygen is always present for passenger comfort, and

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must also extract smoke quickly and efficiently in the eventof fire. All this requires co-ordination between station andtunnel designers, architects, rolling-stock engineers andenvironmental-control engineers to produce a feasiblesystem. Much computer-modelling work is required onairflow and heat transfer, and consultants are equipped toundertake the very complex calculations required toensure that the individual items of equipment, i.e. fans,chillers, train-borne equipment, vent shafts and air pass-ages, are adequate and compatible.

9 Co-ordination of all electrical and mechanicalengineering

The power supply must be tailored to the requirements ofthe trains and the static equipment. Interference betweenthe various electrical subsystems must be kept to anacceptably low level. The passenger throughput capacity ofautomatic fare-collection equipment, escalators and trains,must all be compatible. The electrical and mechanicalequipment must fit logically into stations and tunnels, andprovision must be made for maintenance and eventualreplacement of the equipment. There are so many variablesthat the preliminary design of the system is necessarily aniterative process, aided by computer analysis to determinethe best combination of many design criteria. Rarely willthese be perfect for any particular system or subsystem,and the consultant must be sufficiently experienced toallow flexibility and compromise without endangering thesuccess of the project.

The consultant must ensure that all the interfacesbetween subsystems are fully defined and that, so far as ispossible, standardisation of operating and maintenancetechniques and procedures is obtained. A particular chal-lenge exists to ensure such compatibility where equipmentmay be purchased from a number of countries, but if atten-tion is first paid to this at the specification stage andduring subsequent stages up to installation, satisfactoryresults can be obtained. Such aspects are an importantfunction of the consultant as project manager.

10 Civil engineering integration with electrical andmechanical works

The engineering departments of existing railway or masstransit organisations tend to be organised throughseparate streams of civil, electrical and mechanical engi-neering, with variations such as signalling and telecommu-nications, electrical power, and mechanical departments.These are further complicated by divisions between repairand new works on the one hand, and operations and main-tenance on the other. Consultants are accustomed toapproaching any multidisciplinary project by organisingcombined teams of all the appropriate skills. It is a veryold truism that all projects are different, while all projectsof a like nature do have common features. Nowhere is thisbetter illustrated than in a new mass transit railway.

It is probable that the apogee of multidisciplinary activ-ity, and hence the need for the co-ordinated efforts of themaximum number of consultants, is in the feasibility stageof planning. Routes having been identified and passengerflows along those routes determined by the transportplanner, it would then be not unusual for the commercialdepartment, having expressed their views on desirabletrain frequency, and the mechanical engineer to proceedwith the design of trains of appropriate capacity to carrythe forecast traffic. At this stage there is a good example ofwhere the integrated approach of the consultants would

bring together the civil, electrical and mechanical engi-neering skills to determine the optimum train width andlength, taking into account the cost of construction of theappropriate size tunnels, width of platforms and length ofstations, together with the cost of the train. All thesefactors are interdependent and require firm overall controlby the consultant managing the project, to ensure that theoptimum size of train, tunnel and station is reachedwithout either excessive innovation or automatic adher-ence to past practice.

Another important aspect of collaboration betweencivil, electrical and mechanical engineering professions is inthe field of the environmental-control system and in theprovision of plant rooms for underground stations. Thesize of ventilation plant, especially in tropical countries, isso large that it can have a significant effect on the size andhence cost of the civil engineering works of an under-ground station.

Although the environmental-control system is one ofthe largest features of the electrical and mechanical ser-vices in the station, the great complexity of current stationdesign, including automatic fare-collection systems, highstandards of lighting, telecommunications, closed-circuittelevision and fire and security alarms, quite apart fromthe basic power supply to operate the trains, makes thevarious types of switchgear, relay and plant roomsrequired at each station complex, interrelated and in totalvolume significant relative to the size of the station. Thusvery close working of all types of engineering skills isnecessary to produce the optimum solution.

Yet another aspect requiring close co-ordinationbetween civil, electrical and mechanical consultants is thedesign of the trackwork and rolling stock, with their inter-relationship.

This collaboration and co-ordination has, of course, tocontinue beyond design into the construction stage. Acomplex railway is an excellent example of a 'chain' type ofproject, where, if a link is missing, the whole project maybe useless. Detailed planning and programming is essen-tial. Fig. 1 shows two ways of drawing master programmesemphasising this interdependence.

11 Architectural aspects

Although the architect is generally acknowledged as anessential member of the team above ground, at least oneclient has been known to query the need below ground. Inmany of the older underground railway systems particular-ly, there was seen to be no need for anyone in the structur-al and building field, other than a civil engineer trained byexperience to deal with the peculiarities arising from thistype of transport. That is not the approach of an experi-enced consultant, who sees a strong architectural elementas an essential part of the planning team. This, of course, isobvious if one goes back to fundamentals and recognisesthat the success of a mass transit system, particularly anunderground railway, can be measured by whether itcarries the maximum number of passengers possible onthat route. Whatever the fare level may be, relative toother transport modes, the best system will be that carry-ing the most passengers, and most passengers will becarried by the system which, in addition to providing afrequent and reliable service, offers convenience, comfortand an attractive travelling environment.

These aspects are the prime concern of the architect,whose task is to ensure that the passenger can quickly andeasily find his way between station entrance and train inclean, well-lit, pleasant surroundings, which may on

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occasion be interesting, even stimulating. He will ensurethat access to the unseen station is readily identifiable atstreet level, and be particularly concerned with the qualityof the lighting to the underground spaces. The traditionalapproach to lighting design as an offshoot of the signallingdepartment is now giving way to the authority of thespecialist lighting engineer in collaboration with the archi-tect on the consultant team. But he is only one of thebuilding services team, who must work closely with thearchitect.

The very character and 'persona' of the system is deter-mined by the interior architecture, in which the integrationof the functional elements of lighting, signing and finishescreates the decorative counterpart to the more utilitarianpassenger-handling elements of ticket machines and bar-riers, control kiosks and escalators.

Thus architects having experience in these fields areessential in the planning team right from the very begin-ning if the end result is to be of high quality.

12 Industrial and graphic design and a house style

To complete the task of making the system efficient andattractive to passengers, two other important aspects needto be considered: industrial design and graphic design.

The industrial designer in the consultant team is con-cerned mainly with the detail of the system, ensuring thatthe hardware, the components and equipment in use bypassengers and staff, is co-ordinated in design for efficiencyin ergonomic and manufacturing terms, and visualharmony and satisfaction in form, finishes and colours.Industrial design is an extension of, and complementary to,the architect's and engineer's work. However, lookingworldwide, the comprehensive results do not generallyindicate the successful efforts of a single designer. Thisaspect is, of course, difficult, stemming largely from theproblem of getting industrial design considered systemati-cally throughout the system, because it is so often the prac-tice to combine the wide variety of equipment from many

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manufacturers, each working on the principle for shapeand colour enunciated so famously by Henry Ford, that'you can have any colour you like as long as it is black'. Ifthat attitude cannot be altered then it is even more impor-tant that the ancillary items, such as station furniture, aredesigned to harmonise with what cannot be changed.

The work of the graphic designer is perhaps morereadily recognised; everyone expects the system to have asymbol, and notices and signs to be provided. But theresponsibility is more than just the choice of lettering andthe design of the route map. It covers all aspects ofpassenger/management communication, from basicrailway and bus information for the traveller to the pro-motion of the organisation itself. One of those aspects isthe development of a system identity or 'house style', bywhich every facet of the undertaking will be recognisedand advertised.

British Rail is a well-known example of how consul-tants, by approaching the problem on a comprehensivebasis, successfully created a new image for a visually mori-bund authority. On a new system or the comprehensiverefurbishment of an existing system, the graphic designer'stask begins with the functional problems of how to directpeople about the system, to establish the most convenientand legible means of identifying routes and destinations.Against the complexity of the network, he considers thepassengers, their literacy, the use of pictograms wherewords can be avoided, and colour for simple coding of thenetwork routes and passenger-handling flow control. Fromits 3-dimensional genesis with architect and industrialdesigner, the house style develops with further attention todetail, the refinement of letterforms and the symbol or logoand their innumerable applications, from tickets to station-ery and staff uniforms to car livery.

13 Construction

The construction of a new mass transit system is a majorcapital undertaking for the economy of any country. Evena small extension to an existing mass transit system is amajor capital investment for the owner. There are somecountries in which more or less fixed, relatively smallannual budgets are allocated to the construction of suchprojects, thus resulting in a long construction period andan overall noneconomic project. In such cases, consultantsare unlikely to be involved. In the normal case, themaximum of volume of construction per annum is themost desirable. What the maximum should be may bedetermined by a number of factors, including the obviousone that the rate of construction of the mass transitsystem, superimposed on other construction projects,should not in itself lead to an acceleration in constructioncosts or the inflation rate. These aspects ought to be exam-ined by the consultant in the feasibility study stage, andnot determined independently by government sourceswhich have imposed on the mass transit authority an arbi-trary rate of expenditure. Once the principle of startingconstruction has been accepted, the civil engineeringdesign and construction methods should be chosen toachieve the earliest date for completion; it is unlikely thatthe different methods of construction which might be con-sidered will cost such different sums that the financialsaving of the cheapest will outweigh the benefit which willattach to the quickest method. The capital sums whichhave to be committed, often in borrowed money, beforethe project begins to earn revenue, are so large that high-interest rates due to prolonged construction can make anotherwise viable project impossible to justify.

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Selection of the appropriate methods of civil construc-tion must be made at the design stage, preferably by con-sultants with experience of different types of constructionused on other systems, and wide enough experience toassess those which are appropriate to the ground condi-tions of a particular project. For these reasons, anauthority experienced in the construction of only its ownsystem is unlikely to have the expertise to determine theoptimum method for a major extension, although it maywell be able to choose one which is technically satisfactory.

Even if a large project of, say, 60 km is planned to bebuilt continuously, it must be planned for completion andoperation in stages, since the first stage might be com-pleted in 4 years while the whole might take 8 years. Ifchanged financial circumstances require a break in con-struction to be made, there will be a planned point avail-able. Such factors would be taken into account by theconsultant when planning the system. Fig. 1 illustrates howsuch stages are built into the overall programme.

Once construction has been started there should belittle delay in carrying it out to a rigid programme forworks at ground level or elevated. One writes 'should' onlybecause it seems unfortunate that whereas the technicalability to plan construction to a comprehensive prog-ramme has become more capable, it appears to bematched with unforeseeable delays, caused by failing toobtain access to the site for legal reasons or by the activ-ities of environmental pressure groups. Nevertheless, boththese causes of delay can be minimised if they are investi-gated thoroughly by consultants during the planning stage,to ensure that all aspects are examined during the feasi-bility study.

Underground construction is another matter, and by itsvery nature delays are possible due to the ground condi-tions turning out to be somewhat different metre by metrefrom those anticipated, however extensive the preconstruc-tion investigations might have been. A good consultantwill advise extensive preconstruction investigations tominimise this risk.

Arguments have been put forward for the client tosupervise construction, so that he may be very closelyinvolved in foreseeing potential delays and investigatingthe causes of delays when they have arisen. It is very oftenthe case that once a delay has occurred for any reason, thetime lost may be minimised or wholly recovered by spend-ing money, but clients seem generally more ready to spendextra money if advised by their own staff rather than byconsultants.

The reluctance of clients to spend money to recoverdelays should not be considered one which afflicts onlyrailway authorities, since electricity and highway authori-ties are equally susceptible to resisting the expenditure,even when, in the case of electricity authorities, the finan-cial consequence of delay in obtaining output from a newpower station can be clearly calculated. Such bodies oughtto be influenced more by the opinion of outside expertconsultants than their own staff, but experience in manycases indicates that such is not the case. Management con-sultants and quantity surveyors, wearing the fashionablecost-consultant hats, have been used in attempts to solvethis dilemma. The author suspects that consultants in psy-chology, advising on why the client has such attitudes,might be more effective.

14 Organisation

Engineering and operations consultants can devise anorganisational scheme for the management and operation

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of the mass transit system being designed. It is indeednecessary for them to do so as a preliminary to preparing astaffing plan for determining the areas and facilitiesrequired for their accommodation. There is much to besaid for those plans being reviewed by specially appointedmanagement consultants with experience in these fields, tostudy not only staffing plans and the facilities required bythe staff, but more importantly the systems which the staffwill be required to operate. With the ever-growing com-plexity of equipment, especially electronic devices, itbecomes all too easy to devise a staffing system which hadits origins in manual methods of administration and oper-ation of a railway, while adding to them the modernequipment and concepts which make many of the manualfunctions unnecessary, and the men to carry them outredundant.

15 Operation

The type of operation will depend on the availability ofsuitable staff, the behaviour patterns of potential pass-engers, the environment and the infrastructure and degreeof support given to the railway to supplement the fare-boxreceipts. These various factors will be analysed by the con-sultant at an early stage, and the preferred options willhave an important influence on the design of the variouselectrical and mechanical subsystems.

The sophistication of the industries in the country todeal with repairs, maintenance and replacement of modernelectronic and other equipment will also be a factor to takeinto account.

If the new mass transit railway is an extension to anexisting system or perhaps just in the same country, manyoperating practices and decisions will follow local prece-dent. In a new system particularly, where there is no exist-ing operating experience, the appointment of a consultantwith such experience is essential during the early stages ofdesign. Ideally, his role will continue and expand untilafter the system has begun carrying fare-paying passengers.

16 Establishing and maintaining financial viability

This subject has been treated last as it is probably the mostimportant, since it is hardly likely now that any masstransit system will be built outside a totalitarian countrywhich cannot be shown to have financial viability by someyardstick. Ideally this is likely to be financially self-supporting but, more practically, will require governmen-tal financial support of a known amount. Some of themore straightforward aspects of establishing financial via-bility form part of the feasibility stage of investigating thejustification for a system. While engineers and economistswill have their traditional parts to play in these roles, thegreater financial complexity, especially the internationalaspects of currency and interest rates, requires consultantsof wide experience in capital markets, such as are found inmerchant banks.

Financial viability may be maintained during the con-struction and operating phases of a system if the manage-ment is of adequate calibre, but unless the managementhas recent experience of other fields or maintains throughmembers of its board, or in other such ways, close contactwith the developing techniques of financial control andmanagement, the overall viability of a mass transit systemmay well decline. Periodic reviews by outside specialistconsultants are the best way of making sure that bad prac-tices do not creep in and become established as normal orunavoidable.

17 Acknowledgments

The author acknowledges with gratitude the major contri-butions and helpful criticisms received from Alan Cottonof Kennedy & Donkin, Douglas Kennedy of Halcrow Foxand Associates and Robert Yuill of the Design ResearchUnit, but is himself responsible for opinions and any con-tentious statements.

412 IEE PROCEEDINGS, Vol. 131, Pt. A, No. 6, AUGUST 1984